Dynamic frequency spectrum re-allocation

ABSTRACT

A method of dynamically re-allocating a frequency spectrum to a plurality of radio networks (RNs;  16 ) in accordance with a predefined spectrum allocation scheme is described. A spectrum resource is previously allocated to each RN ( 16 ) or group of RNs ( 16, 16 ′). An electronic spectrum request for a RN ( 16 ) or a group of RNs ( 16, 16 ′) is generated and transmitted via a communications network ( 18 ) to a server infrastructure ( 12 ) which also receives electronic spectrum requests for other RNs ( 16 ), the server infrastructure ( 12 ) processing the received electronic spectrum requests in accordance with the spectrum re-allocation scheme to re-allocate the spectrum resources to the plurality of RNs ( 16 ).

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates to the field of allocating a frequency spectrum toa plurality of radio networks. More particularly, the invention departsfrom the situation that a spectrum resource has previously beenallocated to each radio network or to a group of radio networks andproposes a method and a system for dynamically re-allocating thefrequency spectrum.

2. Technical Background

In recent years wireless communications expanded rapidly and the currentdevelopment shows clear signs of accelerated future growth. However,future growth is limited by the fact that the total frequency spectrumthat is made available for wireless communications cannot keep pace withthe increasing demands. There have thus been various approaches likechannel splitting or advanced speech and data coding to improve spectrumefficiency. Additionally, technical improvements enable wirelesscommunications to advance into increasingly higher frequency regions. Inspite of all these attempts, spectrum resources have become scarce.

Due to the steadily increasing spectrum demands spectrum allocation hasbecome an important topic. Basically, spectrum allocation belongs to thecategory of problems that concern the distribution of a scarce resourceto a set of individuals having different demand for the resource.

In the past several approaches like beauty contests and auctions havebeen employed in order to allocate a frequency spectrum to a certainnumber of competing spectrum applicants (e.g. operators) for usage bytheir radio networks (RNs).

A beauty contest is a spectrum allocation scheme which is generallybased on the spectrum applicant's prospects of the spectrum usage overseveral years and also on the related interests of governments. Thecomplex nature of such beauty contests requires a long-term allocationof the spectrum resources.

As an alternative to beauty contests many governments have made use ofauctioning schemes. Such schemes involve the auctioning of a pluralityof spectrum licenses for typical license periods ranging from ten totwenty years. The settlement price of such auctions reflects theexpected earnings from the services provided in the licensed spectrumover the license period.

As has become apparent from the above, the currently practiced long-termspectrum allocation schemes are not appropriate for dynamic spectrumallocation. If for example technical developments necessitate short-termre-allocations of the frequency spectrum allocated by means of thespectrum allocation schemes discussed above, such re-allocations cannotbe dynamically performed today.

There is, therefore, a need for a method and a system for dynamicallyre-allocating a frequency spectrum to a plurality of RNs, which is moreflexible and can easily be adapted to the ever-changing demand forspectrum resources.

SUMMARY OF THE INVENTION

According to the invention this need is satisfied by a method ofdynamically re-allocating an at least partially continuous frequencyspectrum to a plurality of RNs in accordance with a pre-defined spectrumre-allocation scheme, wherein a spectrum resource has previously beenallocated to each RN and wherein the method comprises generating anelectronic spectrum request for a RN and transmitting the electronicspectrum request via a communications network to a server infrastructurewhich also receives electronic spectrum requests for other RNs, theserver infrastructure processing the received electronic spectrumrequests in accordance with the spectrum re-allocation scheme in orderto re-allocate the spectrum resources to the plurality of RNs.

In contrast to dynamic frequency re-allocation schemes like DynamicFrequency Selection (DFS), which re-allocate a single frequency withinthe spectrum resource available to a single RN, the invention proposesto dynamically re-allocate a continuous frequency spectrum. Thiscontinuous frequency spectrum is re-allocated among two or more RNs.

The invention departs from the situation that a frequency spectrum hasalready been allocated to a plurality of RNs, for example by means ofone of the long-term spectrum allocation schemes known in the art or anyother allocation scheme, and proposes to continue with a dynamicspectrum re-allocation scheme that is based on electronic spectrumrequests submitted to a central authority via a communications network.The central authority evaluates the received spectrum requestspreferably in real-time and re-allocates spectrum resources toindividual RNs or individual groups of RNs. The use of electronicspectrum requests and the automated evaluation thereof constitutes theframework which enables the implementation of dynamic, i.e. short-term,re-allocations of a frequency spectrum.

According to the dynamic nature of this invention, re-allocations may beperformed continuously, for example on a day-to-day basis, or at leastquasi-continuously like during scheduled re-allocation periods. Comparedto the current re-allocation periods ranging between ten and twentyyears the quasi-continuous re-allocations are performed in much shorterintervals of preferably one year or less. In the case re-allocation isperformed quasi-continuously, specific submission periods may be definedduring which the electronic spectrum requests may be submitted to or areaccepted by the server infrastructure. Such submission periods may rangebetween one or more days and several weeks or months.

Due to the dynamic nature of the spectrum re-allocation, technical needsof RNs and economical needs of RN operators can be satisfied almost inreal-time in the case the re-allocation is performed continuously. Ifthe re-allocation is performed quasi-continuously, the operators maystill plan more flexibly because they basically have only to considertheir spectrum needs until the next spectrum re-allocation process.

The electronic spectrum request submitted to the server infrastructuremay comprise an indication of the specific size of the spectrum resourcerequested for a particular RN. Alternatively, it may simply indicatethat a spectrum resource is needed for a particular RN withoutspecifying the size.

The electronic spectrum request is generated on the basis of variousconsiderations. One of those considerations may be the service qualityof a RN, which also depends on the actual or predicted traffic on theRN's spectrum resource. The electronic spectrum request may thus begenerated in dependence of the service quality. This means that if forexample the operator of a RN expects increasing traffic on his RN, hemay submit an electronic spectrum request that takes this additionaltraffic into consideration and vice versa. Apart from the servicequality, or in addition to the service quality, aspects like improvedspectrum efficiency of a particular RN or strategic considerations mayalso form the basis for a specific electronic spectrum request.

In most cases the spectrum resource available to a particular RN canonly be increased at the expense of the spectrum resource currentlyallocated to one or more other RNs. Re-allocation therefore necessitatesthat the whole frequency spectrum or at least a portion thereof isdynamically reallocated among the RNs.

If only a portion of the frequency spectrum is to be reallocated, aspecific re-allocation ratio may be defined. This re-allocation ratioindicates the portion of the previously allocated frequency spectrumthat is to be dynamically re-allocated, whereas the remaining portion ofthe total frequency spectrum is not subjected to the re-allocationprocess.

In the case only a portion of the frequency spectrum is reallocated,this portion has to be taken from the individual RNs' spectrumresources. This is preferably done in accordance with a predefinedcontribution scheme. This predefined contribution scheme may for exampledefine that each RN has to contribute the same spectrum amount or thateach RN contributes a spectrum amount that is proportional to thespectrum resource currently allocated to this RN.

The spectrum re-allocation scheme underlying the dynamic re-allocationprocess has to be chosen such that short-term allocation is renderedpossible. Various re-allocation schemes fulfill this requirement.

According to a first exemplary variant, the spectrum re-allocationscheme is based on spectrum credits that relate to elementary spectrumunits. According to this spectrum re-allocation scheme, each RN or groupof RNs may be assigned the same or an individual number of spectrumcredits that are exchangeable into a specific spectrum resource. Anelectronic spectrum request in this spectrum re-allocation scheme maythus comprise a specification of a particular number of spectrum creditsrepresentative of the requested spectrum resource.

Preferably, the communications network linking the RN to the server'sinfrastructure (and, if required, additionally linking individual RNs)and the system as a whole are configured such that they allow toreassign the spectrum credits among the plurality of RNs. Such animplementation enables spectrum credit trading and thus guarantees aneconomically equitable access to spectrum resources. In order to preventspecific RNs from blocking other RNs, the spectrum credits may have alimited temporal validity. Furthermore, the number of spectrum creditsthat may be allocated to a specific RN could be limited.

According to a second exemplary embodiment, the re-allocation scheme maybe auction-based such that the electronic spectrum requests submittedvia the communications network comprise electronic bids. The frequencyspectrum to be re-allocated may be auctioned as a single bundle or itmay be divided into a plurality of frequency bundles which are auctionedseparately. The electronic bids may relate to one or more frequencybundles comprised within the frequency spectrum.

A specific frequency bundle may be re-allocated to this RN or this groupof RNs associated with the best electronic bid. The best electronic bidneed not necessarily be the bid specifying the highest price. Instead,the best electronic bid may be determined on the basis of one or morefurther parameters like the RN's previous quality of service.

Once one or more specific frequency bundles have been auctioned by theRN associated with the best electronic bid, it might become necessary tore-allocate these one or more frequency bundles, or a part thereof,prior to the next (scheduled) re-allocation process in which all RNstake part. Such a situation may arise for example if the RN associatedwith the best electronic bid is not willing to use or not capable ofusing the obtained spectrum resource adequately because the spectrumresource was primarily acquired to block other RNs. In order to preventsub-optimal quality of service, one or more frequency bundles might bede-associated from this RN in exchange for a predefined penalty orrestitution. The penalty may be of a financial nature.

According to a further aspect of the auctioning scheme the frequencyspectrum to be auctioned may be partitioned bid-proportionally. Thismeans that a larger spectrum resource is re-allocated to a RN associatedwith a better bid and vice versa. In order to avoid fragmentation, aminimum quantity for an acceptable electronic bid or a minimum partitionsize may be defined or dynamically specified.

The submission of the electronic bids may be performed in a single roundor in a plurality of subsequent rounds. In the latter case theelectronic bids submitted by an operator of a specific RN are submittediteratively in response to previous electronic bids submitted byoperators of other RNs.

The invention can be implemented as a hardware solution or as a softwaresolution. The software solution includes a computer program productcomprising program code portions for performing the method set outabove. The computer program product may be stored on a computer readablerecording medium like a hard disc, a CD-ROM, a floppy disk or on anyother storage device.

The hardware solution is constituted by a system for dynamicallyre-allocating a frequency spectrum to a plurality of RNs, the systemincluding a communications network and at least one RN infrastructurewith one or more RNs, means for generating an electronic spectrumrequest, and means for transmitting the electronic spectrum request viathe communications network. The system further includes a serverinfrastructure in communication via the communications network with theat least one RN infrastructure, the server infrastructure having meansfor receiving electronic spectrum requests and means for processing thereceived electronic spectrum requests in accordance with the spectrumre-allocation scheme to re-allocate the spectrum resources to theplurality of RNs. Preferably, the system is configured as an electronicauction network.

The invention may also be realized in the form of a RN infrastructureconfigured to communicate with a server infrastructure and vice versa

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages of the invention will become apparent upon referenceto the following description of preferred embodiments of the inventionin the light of the accompanying drawings, in which:

FIG. 1 shows a schematic view of a system according to the invention fordynamically re-allocating a frequency spectrum;

FIG. 2 schematically shows the course of a quasi-continuous spectrumre-allocation according to the invention (time axis); and

FIG. 3 schematically shows the frequency spectrum to be re-allocated toa plurality of radio network infrastructures (frequency axis).

DESCRIPTION OF PREFERRED EMBODIMENTS

In the following the invention is exemplarily set forth with respect toRNs operating in licensed spectrum bands. The RNs can be constituted bymobile radio networks (GSM, TDMA, PDC, CDMA, EDGE, WCDMA etc.),broadcast networks (DVB, DAB, etc.) or fixed access networks (LDMSetc.).

In FIG. 1 a system 10 according to the invention for dynamicallyre-allocating a frequency spectrum to a plurality of RNs 16, 16′ inaccordance with a predefined spectrum re-allocation scheme is depicted.The system 10 comprises a server infrastructure 12 associated with aplurality of RN infrastructures A, B, C, D. The number of RNinfrastructures associated with the server infrastructure 12 may belimited, preferably to a maximum number of ten RN infrastructures. Inthe embodiment depicted in FIG. 1, the server infrastructure 12 isassociated with four RN infrastructures A, B, C, D.

Each of the RN infrastructures A, B, C, D depicted in FIG. 1 is operatedby a different RN operator and comprises a client component 14 and atleast one RN 16, 16′. The client component 14 allows to generate anelectronic spectrum request and includes an interface device fortransmitting the generated electronic spectrum request to the serverinfrastructure 12.

The client components 14 and the server infrastructure 12 communicatevia a communications network 18. The communications network 18 may be apublic network like the Internet or a dedicated internal network forfrequency spectrum re-allocation purposes. If the communications network18 is constituted by a public network, security requirements maynecessitate an encrypted communication between the client components 14and the server infrastructure 12. Additional components like firewalls,proxy servers and demilitarized zones (DMZ) could be used to preventunauthorized access to the client components 14 or the serverinfrastructure 12. In order to improve authorization security, eachclient component 14 could be provided with smart card technologyincluding a secure and user-controllable card reader (not depicted inFIG. 1).

It should be noted that in the embodiment depicted in FIG. 1 the clientcomponents 14 can communicate with each other via the communicationsnetwork 18 and the server component 12. The server component 12functions as a central authority that controls the communication amongthe client components 14. In principle, the client components 14 couldcommunicate directly with each other if direct communication linksbetween the client components 14 are provided.

Any electronic spectrum requests transmitted from the client components14 via the communications network 18 to the server infrastructure 12 arereceived by an appropriately configured interface device of the serverinfrastructure 12 and are processed in accordance with a predefinedspectrum re-allocation scheme by a processing device of the serverinfrastructure 12. In the course of this processing, spectrumre-allocation information is generated and transmitted back via thecommunications network 18 to the client components 14.

Prior to considering some exemplary dynamic spectrum re-allocationschemes in more detail, some exemplary generic aspects of all schemeswill be considered with reference to FIGS. 2 and 3.

In FIG. 2 an exemplary quasi-continuous re-allocation scheme isdescribed with reference to a time axis t. At an initial point in timet₀ it is assumed that the frequency spectrum is already completely or atleast partially allocated to the four RN infrastructures A, B, C, Ddepicted in FIG. 1. The operators of the RN infrastructures A, B, C, Dhave been informed that the frequency spectrum or at least a partthereof is re-allocated starting from a point in time t₅ and thatelectronic spectrum requests for desired spectrum resources may validlybe transmitted, and are accepted by the server infrastructure 12, duringa time interval Δt₁ preceding t₅. The next re-allocation takes place att₉ and electronic spectrum requests relating to t₉ may be validlysubmitted during Δt₂. Starting from t₅, the re-allocation is performedquasi-continuously in constant time intervals of four time units, i.e.t₉−t₅. One time unit (t_(i)−t_(i-1)) may correspond to for example oneweek or one month.

According to an embodiment not shown in the drawings the re-allocationprocess could also take place continuously and may for example involveonly two of the RN infrastructures A, B, C, D depicted in FIG. 1.

For example an RN infrastructure which requires a larger spectrumresource may at any point in time transmit a corresponding electronicspectrum request to the server infrastructure 12, which forwards theelectronic spectrum request or processes the electronic spectrum requestand forwards the processed electronic spectrum requests to one or moreof the further RN infrastructures. Should one or more RNsinfrastructures be willing to abandon a part of their spectrumresources, they may notify the server infrastructure 12 accordingly viathe communications network 18. The server infrastructure 12 may thenimmediately (i.e. not bound by fixed points in time t_(i)) re-allocatethe spectrum resources appropriately between the RN infrastructurerequesting the spectrum resource and the one or more RNs infrastructurewilling to abandon their spectrum resources.

In FIG. 3 a possible outcome of a re-allocation process is exemplarilydepicted. In the embodiment shown in FIG. 3 the frequency spectrum Δf tobe dynamically re-allocated is arranged between the lower frequencylimit f₀ and the upper frequency limit f₁. It is assumed that thefrequency spectrum Δf has been divided into equidistant frequency blocksΔf₁, Δf₂ . . . which in the exemplary embodiment depicted in FIG. 3constitute elementary spectrum units. Of course, the frequency spectrumΔf could also be divided non-equidistantly.

As becomes apparent from FIG. 3, RN infrastructure D of FIG. 1 has beenallocated two elementary spectrum units, namely Δf₁ and Δf₂. RNinfrastructure B of FIG. 1 has been allocated three elementary spectrumunits, and the remaining RN infrastructures A and C share the remainingelementary spectrum units not explicitly shown in FIG. 3.

In principle, the frequency spectrum Δf could also be fragmented.However, it is assumed here that such a fragmentation can be removed byappropriate defragmentation processes.

In the following description, two dynamic spectrum re-allocationschemes, namely a short-term auctioning scheme and a spectrum creditbased scheme, will be described in more detail.

1. Short-Term Auctioning Scheme

According to the short-term auctioning scheme, the operators of the RNinfrastructures A, B, C, D of FIG. 1 participate in an electronicauction by submitting electronic spectrum requests in the form ofelectronic bids. The electronic bids can be submitted in a single roundor iteratively in multiple rounds.

As depicted in FIG. 2, bidding is performed during predetermined periodsof time Δt_(i). The spectrum resources to be auctioned during Δt_(i) aretaken from spectrum resources the operators have obtained prior to thebeginning of Δt_(i). The size of the total spectrum resources availablefor auctioning is not discussed here further.

1.1 Bid-Proportional Spectrum Partitioning

In the following a bid-proportional re-allocation of the spectrumresources available for bidding is described. According to thisembodiment, the entire frequency spectrum that is available for dynamicre-allocation is auctioned during each scheduled auctioning intervalΔt_(i). During each interval Δt_(i) each operator places bids for aportion of the available frequency spectrum.

In the case all participating operators refrain from revising their bidsfurther, or in the case the time interval Δt_(i) has expired, the totalamount of the offered frequency spectrum is partitioned directly inproportion to the bids of the individual operators and distributed tothe operators accordingly. However, in order to avoid fragmentationeffects, the total number of partitions is limited and a specificminimum size of each partition is to be specified.

During the bidding process, each operator i can determine the spectrumpartition S_(i) he would get from the total amount of dynamicallyre-allocated frequency spectrum S for his bid B_(i) if the otheroperators j would stick to their bids B_(j) in accordance with thefollowing exemplary formula:$S_{i} = {{f\left( B_{i} \right)} = {\frac{B_{i}}{B_{i} + {\sum\limits_{j \neq i}B_{j}}}S}}$

The price B_(i) an operator is willing to pay thus directly determinesthe size of the spectrum resource the operator will receive. Eachoperator will consider in his bids the individual revenue he expects toget from the spectrum resource he desires in the time interval betweentwo subsequent re-allocations.

At the end of the auction the operators are informed of the spectrumresource re-allocated to their respective RN and requested to pay inaccordance with their (last) bid. The total amount paid or a fractionthereof may be refunded to the operators at the end of each auctioningprocess or to third parties such as the government. The scheme accordingto which the amount is returned to the operators is preferablyconfigured such that an individual operator cannot predict how much hewill get back. The reason therefore is the fact that if the operatorcould predict the refunding, he would take this into account whenplacing his bids, which is not desirable.

1.2 Bidding for Predefined Frequency Bundles

According to a further variant, the frequency spectrum to be dynamicallyre-allocated is divided into one or more frequency bundles that areindividually auctioned among the operators. The frequency bundles mayhave all the same size or different sizes. For example each frequencybundle to be auctioned may correspond to a frequency block Δf_(i) asdepicted in FIG. 3 or a multiple thereof.

The operators place electronic bids during predetermined submissionperiods Δt_(i) (see FIG. 2) for individual frequency bundles Δf_(i) (seeFIG. 3). The price an operator is willing to pay for a frequency bundleis influenced by his individual business case and other prospects fromthe usage of the frequency bundle between two subsequent re-allocations.

According to an important aspect of this embodiment, the effects ofelectronic bids placed by operators aiming solely at driving the priceare alleviated after the auction process has ended and prior to thesubsequently scheduled auctioning process. This will now be illustratedin more detail.

Generally, the operator with the best (for example the highest) finalbid for a specific frequency bundle has the right to buy this frequencybundle. If he exploits his right, the amount he pays might be given tothe remaining but out-bidded operators or to third parties. On the otherhand, if the operator with the best final bid is not interested inactually buying the frequency bundle this operator is given thepossibility to refrain from buying the frequency bundle in order toavoid the situation that spectrum resources remain unused that arerequired by other operators to ensure optimal quality of service.

However, the operator may only refrain from buying the frequency bundleif he pays a certain fine. This fine should be lower than the loss theoperator would face if he had bought the frequency bundle because if thefine were higher, the operator would rather buy the frequency bundlethan paying the fine. However, if the operator would rather buy thefrequency bundle than paying the fine, the frequency bundle is notoptimally used. This can be avoided by appropriately selecting theamount of the fine.

The amount of the fine should be set so large that the operator is justexpected to select the fine with a high probability. Preferably, theamount of the fine is a certain fraction of the operator's bit. The finepaid by an operator can be distributed among the other, out-bidedoperators according to a specific distribution scheme.

If the operator with the best bid chooses not to buy a frequency bundle,the operator with the second best bid is given two alternatives: Theoperator with the second best bid may either buy this frequency bundleat the price of his last bid or he may not buy this frequency bundle andpass the frequency bundle to the operator with the third best bid. Theoperator with the third best bid then has the same alternatives like theoperator with the second best bid. The remaining operators that havebided may thus also decline from buying the frequency bundle, but incontrast to the operator with the best bid they are not fined fordeclining. The reason for this is the fact that the fine is only neededto discourage each operator from placing a better bid than the currentbest bid if the value of the auctioned frequency bundle to him is lessthan the amount of the bid placed by him.

2. Spectrum Credit Based Re-Allocation Scheme

This spectrum re-allocation scheme is based on spectrum credits thatrelate to elementary spectrum units, for example the frequency intervalsΔf_(i) depicted in FIG. 3.

In this scheme each operator, i.e. each RN infrastructure A, B, C, Ddepicted in FIG. 1, can acquire or simply receives from the serverinfrastructure 12, which acts as spectrum broker, a specific amount ofspectrum credits. The obtained amount of spectrum credits enables usingon the average a certain spectrum resource M_(i) when a certain spectrum(see for example Δf in FIG. 3) is dynamically re-allocated. The temporalvalidity of the spectrum credits is limited by introducing a validityperiod T.

The spectrum credits SC(M_(i)) are given to each operator i at thebeginning of each period T and expire at the end of T. If it is assumedthat M_(i) represents a fraction of the spectrum to be re-allocated andfurther that n RN infrastructures participate in the re-allocationprocess, the sum of all M_(i) (1≦i≦n) equals 1. This means that alloperators i may use exactly the spectrum resource M_(i) in T without anyconflict. In an enhanced scheme, also larger sums than 1 are possible.

If for example an operator i wants to use a spectrum resource N_(i) ofthe frequency spectrum Δf during a period t′<T, the operator i mustspendSC(N _(i))=(N _(i) /M _(i))*(t′/T)*SC(M _(i))spectrum credits. The operator i thus has enough spectrum credits inorder to use either constantly the spectrum resource M_(i) during T, orto use a larger spectrum resource for a shorter period t′<T and asmaller spectrum resource in the remaining duration of T. Spectrumcredits that have not been spent at the end of T are invalidated andcannot be used in a subsequent period T.

Conflicts that may arise in the case where several or all operators wantto spend in t′ more spectrum credits, i.e. want to use a larger spectrumamount, than available in Δf. Such conflicts must be resolved in apredetermined manner, for example according to thefirst-come-first-served principle, according to the short termauctioning mechanism described above or according to other schemes.

Spectrum credits can be re-assigned among the client components 14 viathe server infrastructure 12 depicted in FIG. 1 or directly between theclient components 14. For example, a RN infrastructure may acquirespectrum credits from another RN infrastructure, thus increasing itsfuture spectrum resources. Of course, the spectrum resources of thefurther RN infrastructure will decrease accordingly. This corresponds toa trading of spectrum credits.

Misbehavior of operators has to be prevented. This can be accomplishedby setting upper limits on the number of spectrum credits that can beassigned to an individual RN infrastructure. It can thus be preventedthat one operator which has saved or acquired more spectrum credits thanother operators prevents the other operators in t′ from using anyspectrum resources.

The embodiments described above ensure fair spectrum usage policies,especially on a spectrum market with a small number of participants. Thespectrum re-allocation scheme of short-term auctioning achieves that theoperators can aim at the exact amount of spectrum resource that isneeded, while ensuring that the totally available spectrum resource isallocated such that it is used in the most efficient way. The spectrumre-allocation scheme of spectrum credits, that can be spent, saved ortraded, ensures that an RN can always use a specific spectrum resource.

Modification and alternative embodiments of the invention arecontemplated which do not depart from the spirit and the scope of theinvention as defined by the foregoing teaching and appended claims. Itis intended that the claims cover all such modifications that fallwithin their scope.

1. A method of dynamically re-allocating a frequency spectrum to aplurality of radio networks in accordance with a predefined spectrumallocation scheme, wherein a spectrum resource has previously beenallocated to each RN or group of RNs comprising: generating anelectronic spectrum request for a RN or a group of RNs; and transmittingthe electronic spectrum request via a communications network to a serverinfrastructure which also receives electronic spectrum requests forother RNs, the server infrastructure processing the received electronicspectrum requests in accordance with the spectrum re-allocation schemeto reallocate the spectrum resources to the plurality of RNs.
 2. Themethod of claim 1, wherein the re-allocation is performed continuouslyor wherein the re-allocation is performed quasi-continuously.
 3. Themethod of claim 2, further comprising determining a service quality ofone of the RNs taking into account the actual or predicted traffic onthe RN's spectrum resource and generating the electronic spectrumrequest in dependence of the service quality.
 4. The method of claim 3,wherein the whole frequency spectrum is re-allocated.
 5. The method ofclaim 3, wherein only a portion of the frequency spectrum isre-allocated and wherein the portion of the frequency spectrum to bere-allocated is taken from the individual RNs' spectrum resourcesaccording to a predefined contribution scheme.
 6. The method of claim 5,wherein the spectrum allocation scheme is based on spectrum creditsrelating to elementary spectrum units.
 7. The method of claim 6, whereineach RN or group of RNs is assigned the same or an individual firstnumber of spectrum credits and wherein an electronic spectrum requestfor an RN comprises a specification of a second number of spectrumcredits representative of the requested spectrum resource.
 8. The methodof claim 7, wherein the communications network allows to reassign thespectrum credits among the plurality of RNs.
 9. The method of claim 8,wherein the spectrum credits have a limited temporal validity.
 10. Themethod of claim 9, wherein the spectrum re-allocation scheme isauction-based and wherein the electronic spectrum requests compriseelectronic bids submitted via the communications network.
 11. The methodof claim 10, wherein the electronic bids relate to one or more frequencybundles comprised within the frequency spectrum and wherein a specificfrequency bundle is re-allocated to the RN associated with the bestelectronic bid.
 12. The method of claim 11, wherein, prior to the nextre-allocation process for all RNs, the specific frequency bundle or apart thereof re-allocated to the RN or group of RNs associated with thebest electronic bid is allocated to another RN or group of RNs.
 13. Themethod of claim 10, wherein the frequency spectrum to be re-allocated ispartitioned bid-proportionally.
 14. The method of claim 13, wherein theelectronic bids are submitted iteratively.
 15. A computer programproduct for dynamically re-allocating a frequency spectrum to aplurality of radio networks in accordance with a predefined spectrumallocation scheme, wherein a spectrum resource has previously beenallocated to each RN or group of RNs, comprising program code portionsfor: generating an electronic spectrum request for a RN or a group ofRNs and transmitting the electronic spectrum request via acommunications network to a server infrastructure which also receiveselectronic spectrum requests for other RNs, the server infrastructureprocessing the received electronic spectrum requests in accordance withthe spectrum re-allocation scheme to reallocate the spectrum resourcesto the plurality of RNs.
 16. (canceled)
 17. A system for dynamicallyre-allocating a frequency spectrum to a plurality of radio networks inaccordance with a predefined spectrum re-allocation scheme, wherein aspectrum resource has previously been allocated to each RN or group ofRNs, comprising: a communications network; at least one RNinfrastructure with one or more RNs, means for generating an electronicspectrum request, and means for transmitting the electronic spectrumrequest via the communications network; and a server infrastructure incommunication via the communications network with the at least one RNinfrastructure, the server infrastructure having means for receivingelectronic spectrum requests and means for processing the receivedelectronic spectrum requests in accordance with the spectrumre-allocation scheme to re-allocate the spectrum resources to theplurality of RNs.
 18. The system of claim 18, configured as anelectronic auction network.
 19. A server infrastructure for dynamicallyreallocating a frequency spectrum to a plurality of radio networks inaccordance with a predefined spectrum re-allocation scheme, wherein aspectrum resource has previously been allocated to each RN or group ofRNs, comprising: means for receiving electronic spectrum requests incommunication via a communications network with at least one RNinfrastructure; and means for processing the received electronicspectrum requests in accordance with the spectrum re-allocation schemeto re-allocate the spectrum resources to the plurality of RNs.
 20. Aradio network infrastructure utilizing a previously allocated spectrumresource, comprising: at least one RN; and a device for generating anelectronic spectrum request and for transmitting the electronic spectrumrequest via a communications network to a server infrastructure whichalso receives electronic spectrum requests for other RNs, the serverinfrastructure processing the received spectrum requests in accordancewith a predefined spectrum re-allocation scheme to re-allocate aspectrum resources to the at least one RN.